Michael Phelps is the most decorated Olympian in history with 28 overall medals.

While it's conceivable that someone could break his record, Phelps believes it would be tough because of specialization.

Phelps said he would be glad to see someone else try to make history.

Michael Phelps says he is done with swimming, retiring his career as the most decorated Olympian in history with 28 overall medals, 23 of them gold.

Phelps' medal count puts him way above the next closest athlete, but what if another dominant swimmer were to emerge and compete in four Olympics as Phelps did? Could his count ever be challenged?

For example, if everything breaks right, Katie Ledecky could perhaps challenge Phelps' record. Ledecky already has six medals to her name, five of them gold. She earned a surprise gold in the 2012 London Olympics, then took home five total at Rio 2016.

At age 20, Ledecky could conceivably compete in two more Olympic games after Tokyo 2020, bringing her to 31 years old by the 2028 Olympics, the same age Phelps was at Rio 2016. With the inclusion of the women's 1,500-meter freestyle going forward (Ledecky holds the world record), she could have seven races on the docket at those games.

While speaking to Business Insider, Phelps said he would be glad to see someone break his record, but thinks it may be tough — not simply because he was so dominant — but because the sport is changing.

"It's also getting more challenging I think just because, I guess you have so many people that are starting to specialize in one event or two events," Phelps said. Phelps swam freestyle, butterfly, and individual medleys, plus relays. Some swimmers only tackle one style of swimming, making the feat harder to accomplish.

However, Phelps also pointed out that a lot has to go right to win medals while competing in seven or eight events.

"When you start building a program like that, when you're swimming seven or eight races," Phelps said, "it's just a combination of everything — mental, physical, emotions — that really have to be pretty much perfect throughout that whole eight-day program."

Phelps said he would love to see someone break his record, though, citing an old expression about records.

"I've always said that records are made to be broken," Phelps said. "If it happens, great, I'd love to be there to watch it and witness some of the greats that are probably gonna be in the sport over the next couple of decades."